Tenofovir, an antiretroviral drug, plays a crucial role in most modern HIV treatment and prevention strategies. However, according to a large study funded by the Wellcome Trust, HIV resistance to tenofovir is becoming surprisingly and alarmingly common.

The study was conducted by researchers from Stanford University in the United States and London School of Hygiene and Tropical Medicine in the United Kingdom. Researchers studied 1926 HIV patients worldwide, who are still out of control of their HIV status despite taking antiretroviral drugs. The researchers found that tenofovir-resistant HIV strains were present in 60% of sub-Saharan African patients, compared with 20% of those treated in Europe. About two-thirds of patients with tenofovir-resistant HIV strains also developed resistance to the other two drugs in their regimen. Relevant findings were published online January 28, 2016 in the Lancet Infectious Diseases Journal.

The study suggests that in Sub-Saharan Africa, up to 15% of HIV-treated patients receiving tenofovir-containing drug combinations will have tenofovir resistance in the first year of treatment, and as time progresses, This figure will rise. Tenofovir-resistant HIV strains have also become more prevalent as they can be passed on to others, potentially undermining global HIV control strategies.

The author of the paper, Dr Ravi Gupta, explains, "Tenofovir is a vital weapon in our arsenal against HIV, so it is very worrying to see such a high level of resistance to the drug . It is a very potent drug with few side effects and no good alternative to public health measures is available. Tenofovir is not only used to treat HIV but is also high There is an urgent need for more efforts to address this emerging problem of drug resistance in populations at risk to prevent HIV. "

Drug resistance usually arises when the patient can not take the medication regularly, so to make first-line treatment work, patients generally need to take the medication for at least 85% to 90% of the time. When treatment is interrupted, the HIV virus can become drug-resistant. Previous studies have demonstrated that tenofovir-resistant HIV strains are less likely to proliferate and proliferate under laboratory conditions. However, it is unclear whether this virus is more likely to spread under actual conditions.

In this study, those with compromised immune systems who started treatment with tenofovir had a 50% probability of developing resistance, whereas those receiving tenofovir and certain other antiretroviral drugs The same is true for patients in combination therapy. In many parts of sub-Saharan Africa, particularly in rural areas, drug availability is limited and patients are treated only if they develop advanced HIV disease. The problem is that the patient's immune system is weaker at this stage, so drugs do not fight the virus alone, but instead increase the likelihood of drug failure and drug resistance.

Once a patient's HIV virus is resistant to first-line drugs, then second-line drugs that cost more but have more side effects are treated. Many rural patients do not have access to these medications, so it is important to try to maintain the effectiveness of first-line medications.

Co-author of the paper, Professor Robert Shafer of Stanford University School of Medicine, said: "Public health agencies and global funders have been very effective at extending antiretroviral drug therapy to an ever-increasing number of patients in need." The study highlights There is also a need to take action to ensure that the treatment plan used to treat HIV remains as long as possible. "